I. Field of the Invention
The present invention relates to a dehumidification apparatus.
II. Description of the Related Art
Various dehumidification apparatuses utilizing deliquescent dehumidification agents such as calcium chloride are known. As a typical example of this type of known dehumidification apparatuses, the dehumidification apparatus described in Japanese Laid-open Patent Application (Kokai) No. 10-192641 will now be described referring to FIG. 15.
The known dehumidification apparatus 100 shown in FIG. 15 comprises a container 101 and a cover 102 enclosing an electric fan 115. On the bottom 101a of the container, granular deliquescent dehumidification agent D such as calcium chloride which absorbs moisture in the air is laid.
The container 101 is closed except for an opening 104 formed in the upper portion of the container 101. A cap 106 having a vertically extending cylindrical air-introducing duct 105 is mounted on the container 101 such that the cap 106 covers the opening 104.
The cover 102 comprises a cylindrical air-discharging duct 110 which vertically extends and coaxially nested in the air-introducing duct 105. The distal end of the air-discharging duct 110 protrudes from the distal end of the air-introducing duct 105. The cover 102 includes a lower cover 113 having an air inlet 112 which communicates with an air-introducing passage 111 formed between the outer surface of the air-discharging duct 110 and the inner surface of the air-introducing duct 105. The cover 102 has an upper cover 116 having an air outlet 114 which communicates with the inner side of the container 101 through the air-discharging duct 110. The upper cover 116 harbors the electric fan 115 and a battery 117 which gives the power to drive the fan 115.
In operation, the fan 115 is driven. As a result, air is drawn through the air inlet 112 and the air-introducing passage 111 into the inside of the container 101. The air is then discharged from the apparatus from the air outlet 114 through the air-discharging duct 110. Since the air contacts the deliquescent dehumidification agent D on the bottom of the container, the moisture contained in the air is absorbed by the deliquescent dehumidification agent D and the air is dried. On the other hand, the absorbed moisture is converted to deliquesced liquid and accumulated on the bottom 101a of the container 101.
With this conventional dehumidification apparatus, since the deliquescent dehumidification agent placed on the bottom of the container is immersed in the deliquesced liquid accumulated on the bottom of the container, the dehumidification ability of the dehumidification apparatus is decreased very much by the accumulation of the deliquesced liquid.
Japanese Laid-open Patent Application (Kokai) No. 2-227115 proposes to separate the deliquescent dehumidification agent D and the deliquesced liquid by harboring the deliquescent dehumidification agent D on a porous plate arranged on the upper portion of the container 101 so that the deliquesced liquid drops onto the bottom 101a of the container through the pores formed in the porous plate. Since the deliquescent dehumidification agent D is separated from the deliquesced liquid and so can be kept relatively dry, the ability to absorb moisture is kept high.
However, in both of the above-described known dehumidification apparatuses, as shown in FIG. 15, the air-introducing duct 105 and the air-discharging duct 110 are nested, so that only a small portion of the deliquescent dehumidification agent can contacts the air. As a result, the dehumidification efficiency of the apparatus is low.